Australia, Canada and several European countries have stopped pressuring Cuba over human rights in the hope of winning commercial favours from Havana, according to confidential US diplomatic cables released by WikiLeaks.

The western governments continued to pay lip service to concerns about political prisoners and censorship, but in reality were appeasing the island's communist rulers, said Jonathan Farrar, the US head of mission.

The diplomat made scathing remarks about his colleagues shunning democracy activists, "kowtowing" to the Castro regime and joining what he scornfully termed the "best friends forever" camp.

"The Cuban government has been able to stonewall its independent civil society from foreign visitors who have, for the large part, been all too ready to give in to Cuban bullying and give up on these encounters," Farrar said.

He named and shamed the countries Washington considers offenders in its battle, started half a century ago by JFK, to keep an international squeeze on the island.

"The Australian foreign minister, Switzerland's human rights special envoy and the Canadian cabinet level minister of the Americas not only failed to meet with non-government Cubans, they didn't even bother to publicly call for more freedoms after visiting Cuba in November," Farrar wrote.

Canada had softened its position over the past year, he said, with newly arrived diplomats minimising civil society contacts. "Promoting democracy may play well in political circles in Ottawa but the Canadian government appears to have decided that doing anything serious about it in Cuba under the current regime could jeopardise the advancement of Canada's other interests."

He railed against the European commission for sitting "snugly in the best friends forever" camp and siding with Spain – which seeks warmer ties with Havana – against more hawkish EU members. "Their functionaries share with us their reproach of the 'radical' Swedes and Czechs, with their human rights priorities, and can't wait for 'moderate' Spain to take over the EU presidency."

The US envoy mocked those who claimed to push for human rights in private meetings with Cuban officials. "The truth is that most of these countries do not press the issue at all in Cuba. The GOC [government of Cuba] … deploys considerable resources to bluff and bully many missions and their visitors into silence."

The criticised governments are likely to reject the memo as an example of sour grapes from a country that has seen its Caribbean foe embraced by Africa, Latin America, Asia and increasingly the west. Even Washington's allies consider its embargo a cold war anachronism. "Demented," as one European ambassador put it.

Cuba's opposition is small, fractious and powerless – split between groups who favour hardline US policy and those who think the softer approach of other governments will do more to open up the island.

The confidential US memo said the Castro government was determined to drive a wedge into the EU's common policy on Cuba, which in theory obliges member states to lobby hard for human rights. Britain is among countries that refuse to send a minister to Havana without concessions.

Farrar approvingly categorised this as the "take your visit and shove it" approach. "Germany, the Czech Republic and the United Kingdom may pay a price in terms of lost business and access from their principled stance. Others who stand in this camp have less to lose from sticking it to the Cubans, and include Poland and Sweden."

There is no mention of William Hague, the then British shadow foreign secretary, and Lord Ashcroft meeting senior Cuban officials in Havana last year. The pair did not meet democracy activists, but since taking office Hague has promised to continue the British policy of not sending ministers.

Farrar said those foreign delegations that shunned civil society activists and avoided mention of political prisoners reaped few dividends. "For the most part the rewards for acquiescing to GOC demands are risible: pomp-full dinners and meetings and, for the most pliant, a photo op with one of the Castro brothers. In terms of substance or economic benefits they fare little better than those who stand up to the GOC."

In a separate cable, Arnold Chacon, the American charge d'affaires in Spain, noted Croatia's effort to placate the US by playing down the importance of a trumpeted visit to Havana last year by Stjepan Mesić, Croatia's president at the time. Croatia's ambassador assured the US envoy that the trip had "zero value" and that the visitors were in fact "embarrassed" by the red carpet treatment.